Expand conf namespace

Put rest of conf.hpp in the conf namespace. This is
largely a sed replace, and wrapping from_json in
conf namespace as it failed to build.

Change-Id: I9fe5c7b2fface44618c43af2367035afc39bcb64
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/dbus/dbuspassive.hpp b/dbus/dbuspassive.hpp
index fa9dab7..8cff245 100644
--- a/dbus/dbuspassive.hpp
+++ b/dbus/dbuspassive.hpp
@@ -37,7 +37,7 @@
     static std::unique_ptr<ReadInterface>
         createDbusPassive(sdbusplus::bus::bus& bus, const std::string& type,
                           const std::string& id, DbusHelperInterface* helper,
-                          const SensorConfig* info);
+                          const conf::SensorConfig* info);
 
     DbusPassive(sdbusplus::bus::bus& bus, const std::string& type,
                 const std::string& id, DbusHelperInterface* helper,